Azure Table Storage Overview
Azure Table Storage is a NoSQL key-attribute store that accepts un-structured, semi-structured, and structured data, and stores it as a dataset. It is ideal for applications that require a flexible, scalable, and cost-effective data storage solution for large amounts of non-relational data.
Key Concepts
- Tables: A collection of entities. Tables do not enforce a schema, so entities within the same table can have different sets of properties.
- Entities: A set of properties, similar to a row in a database. An entity can have up to 252 properties, plus three system properties:
PartitionKey
,RowKey
, andTimestamp
. - Properties: A name-value pair within an entity. Property names are strings, and values can be of any of the six supported primitive data types (String, DateTime, Double, Boolean, GUID, Binary).
- PartitionKey: A string that identifies the partition in which the entity resides. Entities with the same
PartitionKey
are co-located on the same storage node, which improves query performance for entities within the same partition. - RowKey: A string that uniquely identifies an entity within a partition. The combination of
PartitionKey
andRowKey
uniquely identifies an entity within a table.
Benefits of Table Storage
- Scalability: Designed to scale to handle massive amounts of data and a high volume of requests.
- Cost-Effectiveness: Offers a very low cost per gigabyte compared to relational databases, making it ideal for large datasets.
- Flexibility: Schema-less nature allows for easy evolution of application data structures without complex schema migrations.
- Performance: Optimized for high throughput and low latency queries, especially when filtering by
PartitionKey
andRowKey
. - Availability: Built on Azure's robust infrastructure, providing high availability and durability.
Common Use Cases
- Storing semi-structured data, such as user data for web applications.
- Storing data for horizontally-scaled applications.
- Storing logs, analytics data, or other time-series data.
- Serving metadata for Blob or File storage.
- Working with Azure Functions or other serverless compute solutions.
Querying Data
Queries in Table Storage are highly efficient when you filter by PartitionKey
. Queries that span multiple partitions are less performant and should be used sparingly. You can also perform complex filtering and sorting using OData syntax.
// Example of inserting an entity (conceptual)
var tableClient = GetTableClient("YourTableName");
var customer = new CustomerEntity("Sales", "Smith_John"); // PartitionKey, RowKey
customer.Email = "john.smith@contoso.com";
customer.PhoneNumber = "425-555-0101";
tableClient.AddEntity(customer);
Pricing Model
Azure Table Storage pricing is based on the amount of data stored, the number of transactions (read/write operations), and data egress. It is one of the most cost-effective storage options for large datasets.
Limitations
- No Joins: Does not support relational database features like joins.
- Limited Data Types: Supports only a limited set of primitive data types.
- No Complex Transactions: Transactions are limited to entities within the same partition.
PartitionKey
carefully to optimize query performance and distribute data evenly across partitions for better scalability.
For more detailed information, including API references and best practices, please refer to the official Azure documentation.